To this date, the known non-lethal and sub-lethal electrical weapons that have been designed to render a target subject less than completely functional have relied on low-frequency, high-voltage currents to shock, stun, or disorient said target subject. An early example of such a device is disclosed in U.S. Pat. No. 3,803,463, to Cover. This device is a handheld weapon from which two small projectiles are fired at the target subject. Each projectile is attached to a fine conductive wire so as to deliver an electrical current to stun said target subject. The principal drawback of this type of device is that only a single shot can be fired without reloading. The weapon is thus of little value if it must be used against multiple targets, if one or both projectiles misses the target, or if the target subject is able to dislodge one or both of the projectiles or their wires before the stunning current is activated. Further, the weapon is classified as a firearm because the projectiles are propelled by nitrocellulose powder charges, and it is therefore subject to all the legal restrictions applied to firearms.
To overcome these difficulties, several non-lethal weapons have been proposed which project two parallel streams of electrically conductive liquid at the target subject. These streams are maintained at different potentials so as to complete a circuit when they contact a target subject and thereby stun said target subject with a series of very low frequency electrical pulses of about 10,000 volts each. Such weapons are disclosed, for example, in U.S. Pat. No. 3,971,292, Paniagua; U.S. Pat. No. 4,486,807, Yanez; U.S. Pat. No. 4,846,044, Lahr; U.S. Pat. No. 4,852,454, Batchelder; U.S. Pat. No. 4,930,392, Wilson; and U.S. Pat. No. 5,103,366, Battochi. The main disadvantage of these weapons is that they can be fired only a few times without reloading. A second disadvantage is that, like the earlier projectile-and-wire device, all these weapons create painful muscle spasms in the target subject that may cause injury, and invite legal action against the users. A third disadvantage is that capillary instability causes the liquid streams to break up into droplets after a short distance. A fourth disadvantage is that gravity quickly pulls such liquid streams into a ballistic arc, thus making aiming difficult. A fifth disadvantage is that the ionic flow within liquid electrolytes provides only weak electrical conductivity. A sixth disadvantage is that the target subject may be wetted by the liquid streams so that the current is short-circuited and unable to stun the subject. A seventh disadvantage is that the electro-mechanical nature of these devices and the corrosive liquids they employ tend to shorten their useful life.
Tetanization is the stimulation of muscle tissue by a rapid series of electrical impulses of such frequency as to fuse individual muscle contractions into a single sustained contraction. Tetanization is a well-known phenomenon: see Offner, "Stimulation With Minimum Power," Journal of Neurophysiology, Vol. 9, pp. 387-390, 1946; Dalziel, "Effect of Wave Form on Let-go Currents," AIEE Transactions, Vol. 62, pp. 739-744, 1943; Dalziel and Lee, "Lethal Electrical Currents," IEEE Spectrum, Vol. 6, pp. 44-50, 1969; Dalziel, Ogden, and Abbott, "Effect of Frequency on Let-go Currents," AIEE Transactions, Vol. 62, pp. 745-750, 1943; Kouwenhoven, Hooker and Lotz, "Electrical Shock Effects of Frequency," Electrical Engineering, Vol. 55, pp. 384-386, 1936; and Ferris et al., "Effects of Electrical Shock on the Heart," Electrical Engineering, Vol. 55, pp. 498-515, 1936.
The present invention also results from prior experiences in the laser-induced ionization of air as described by Koopman and Wilkerson, "Channeling of Ionizing Electrical Streamer by a Laser Beam," Journal of Applied Physics, Vol. 42, pp. 1883-1886, 1971, and Koopman and Saum, "Formation and Guiding of High-Velocity Electrical Streamers by Laser-Induced Ionization," Journal of Applied Physics, Vol. 44, pp. 5328-5336, 1973. Prior applications of laser-induced ionization can be found in U.S. Pat. No. 3,719,829, Vaill and U.S. Pat. No. 3,775,638, Tidman which disclose methods of creating a conductive path in a gas, U.S. Pat. No. 4,017,767 Ball and U.S. Pat. No. 4,453,196 Herr which disclose the transmission of electricity via laser-ionized air channels, and U.S. Pat. No. 5,175,664 Diels et al. which discloses methods of creating conductive paths of ionized air by means of laser beams toward the goal of discharging storm clouds.
This invention also relates to devices used to damage or destroy electronic circuits at a distance. Because such circuits now control many internal combustion engines, high-voltage currents or pulses which damage those circuits necessarily disable the engines they govern. One commercial application is the stopping of fleeing automobiles quickly without causing injury to the passengers or bystanders. High voltages are required because the current must reach ground across a gap of about ten centimeters between the automobile's wheel rims and the roadbed. Because the breakdown voltage of dry air is about 32 kV cm-.sup.1, the potential difference between the wheel rims and the ground is approximately 320 kv. As disclosed by U.S. Pat. No. 5,503,059, prior means of stopping an automobile with an external electric current include placing a conductive pad in its path. As the vehicle passes over, the pad delivers a powerful electric impulse to it and thus to its electronic components. This method has the obvious disadvantage of the user having to choose and reach an effective location before the automobile's arrival. The same U.S. Patent also discloses two other means of conveying an electric current to a moving vehicle. The first is by contacting its undercarriage with metal rods that project from the pursuing police car. The second is by firing into the fleeing auto a harpoon with trailing wires which then transmit electric pulses to it. Each of those methods lacks satisfactory range and the ability to continuously target a moving vehicle. Another prior means utilizes microwave pulses that are directed toward the automobile from an antenna on the pursuing police car. According to U.S. Pat. No. 5,293,527, the width of the beam intended to achieve this goal is approximately 50.degree.. A microwave pulse of this width would not only dissipate too rapidly to be effective at any reasonable distance, but would probably affect other vehicles as well.
The instant invention results from a search for a weapon that would be more efficient in conducting electrical discharges to a distant vehicle within a greater range for a more precise and continuous targeting.